A variety of birth control methods have been utilized in the past in an attempt to prevent undesired conception. Some methods are purely mechanical or involve the implantation of devices which interfere with conception. The present invention is not directed to these methods. Also, the drastic remedy of surgically removing reproductive organs is not the object of the present invention. As hereinafter described, the present invention is directed to a surgical technique which is simple to perform, safe, effective, reversible and relatively inexpensive.
The invention is directed toward a method and apparatus for sterilizing female mammals. In particular, this invention is directed to a relatively simple surgical procedure for human females which may be performed in the physician's office. Successful implementation of the method results in permanent but not irreversible sterility.
One recognized related surgical technique has been to surgically tie off or sever the fallopian tubes so that the ovum may not pass therethrough, and is thus unavailable for fertilization. A disadvantage of this method is that is is a surgical procedure which requires an incision or which may involve the expense and inconvenience of a hospital stay. Even though office or day surgery may be available in some cases, there is always some risk of complications attendant to this surgery. Further, the method is sometimes not reliable because it is known that the mucosal lining of the fallopian tube characteristically tends to regenerate and resume its function.
Another method involves injecting a curable elastomeric composition into the ovaduct in an amount sufficient to fill the portion of the ovaduct adjacent the uterus. The elastomeric composition is allowed to solidify to thereby nonsurgically block the tube. See for example, Erb, U.S. Pat. No. 3,805,767. Another method of blocking the fallopian tube involved the use of a spherical plug as shown in Read, U.S. Pat. No. 3,042,030. These methods present serious reliability questions.
Yet another method of sterilization involves use of one or more catheter carried hypodermic needles which can be inserted into the uterus to a predetermined position at the uterine cornu and the internal tubal ostra followed by injecting a scarifying or sclerosing agent which produces a chronic lesion at that point. See for example, DeFoe, U.S. Pat. No. 4,416,660. Chemical scarifying of the fallopian tube has also been suggested whereby means is provided for injecting into the fallopian tubes a tissue fibrosing promoting material in combination with the gel-forming carrier. The method promotes tissue fibrosis or scarifying and a permanent closure of the tube. See Corey, U.S. Pat. No. 4,185,618. Peritoneal infiltration by the scarifying agent may occur when using this method.
It is also known that thermoelectric devices are available for performing surgical procedures including, for example, electrically cooled cryocautery devices known as peltier cells. See Hirshhorn, U.S. Pat. No. 3,502,080. However, the device shown in Hirschhorn is not adapted for vaginal cauterization.